[1] Morse represented New Hampshire's 22nd State Senate district from 2010 to 2022, having previously held the same office from 2002 to 2006.

In 2022, Morse was a Republican candidate for the U.S. Senate in New Hampshire, placing second in the primary behind Donald Bolduc.

[4][5] He is the owner of Freshwater Farms, a landscaping business and garden center in southern New Hampshire.

[10] He ran for the Executive Council of New Hampshire in 2006, but lost the election to state Senator Beverly Hollingworth.

[14] In 2017, Morse served as acting governor of New Hampshire for two days, from when Maggie Hassan resigned as governor in order to join the United States Senate on January 3, 2017,[1] until Chris Sununu's inauguration on January 5.

[2] It had been widely anticipated that Morse would seek a full term as Governor of New Hampshire in the 2022 election, however incumbent Republican Chris Sununu opted to seek reelection, causing Morse to shift course toward a U.S. Senate run.